The present invention relates to methods and systems for displaying information relating to vasculature, such as blood vessels and arteries, and more particularly to the visualization of coronary arteries.
There are different known imaging techniques for the visualization to display blood vessels in an image. Known techniques are for instance Volume Rendering (VR), multi-planar reformation (MPR), Maximum Intensity Projection (MIP) and shaded surface display (SSD) and can be used to render blood vessels in medical images. Each of these techniques, however, is limited when used in connection with displaying blood vessels, and in particular, when displaying coronary arteries.
By way of example, volume rendering can show parts of coronary arteries as well as background data associated with the coronary arteries, but may involve too much processing to be useful in a clinical setting while the images thus created may involve the risk of obliterating stenoses. Additionally, this rendering technique generally masks out of the displayed image the areas surrounds the vasculature. The lack of surrounding area information can significantly reduce the effectiveness of the visualization, making it difficult to identify the exact location and orientation of the visualized vessels. For example, if only the coronary trees are visible, it can become difficult to distinguish between the left and right sides, or determine which direction is up and which is down.
MPR techniques suffer in that they cannot display multiple arteries unless the arteries are in the same plane. Thus, problems in the arteries can be missed or, in some cases, it may appear that problems are present when there are none.
Other display techniques suffer from inaccuracies in displaying the information. For example, in unfolding techniques, either the distance or the angle associated with the vessel will be inaccurate.
Of the commonly used imaging techniques, MIP is a promising method for the visualization and evaluation of coronary arteries. Whole volume MIP will result in other cavities and vascular structures to overlap the coronaries. Thus masked MIP is preferred. However, masked MIP will only display the coronaries without depth information or their adjacent anatomy.
MIP techniques of projecting images of coronary arteries are disclosed in several articles. See, for example, Etienne, Botnar, Van Muiswinkel, Boesiger, Manning and Stuber, “Soap-Bubble” Visualization and Quantitative Analysis of 3D Coronary Magnetic Resonance Angiograms, Magnetic Resonance in Medicine 48:658-666 (2002), which is hereby incorporated by reference. See, also, Tuchschmid, Martin, Boesiger and Weber, CoroViz: Visualization of 3D Whole-Heart Coronary Artery MRA Data, Journal of Cardiovasular Magnetic Resonance, 2005, 7:220-221, which is hereby incorporated by reference.
Accordingly, new and improved systems and methods for displaying blood vessels with background information, and in particular, simultaneously showing the two coronary arteries with their surrounding contexts, are needed.